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Smart Materials and Devices
Pablo G. Caceres‐Valencia, B.S. Mech.Eng., B.S. Mat.Sc., Ph.D. Mat.Sc.
Course Number INME 5015 and INME 6107
Course Title Selected Topics in Mech. Eng.
Smart Materials and Devices Credit Hours 3 credits
Instructor Dr. Pablo G. Caceres‐Valencia
Office Luccetti L‐212 Phone Ext. 2358
e‐mail pcaceres@me.uprm.edu
Web‐site http://academic.uprm.edu/pcaceres
Office Hours T‐Th 7:30‐10:00am
General Information
Assessment
The course will be assessed in the following manner:
1st Partial Exam 30%
Project 30%
Quizzes 30% (*)
Attendance 10% (**)
(*) Date due WebCT Quizzes (4) and class participation.
(**) After the second missed class, one point will be deducted in the final grade per each missed class (up to 8 points).
Grades Final Grade Range Final Letter Grade
100 – 90 A
89 – 80 B
79 – 70 C
69 – 60 D
59 ‐ 0 F
AttendanceAttendance and participation in the lecture are mandatory and will be considered in the grading. Students should bring calculators, rulers, pen and pencils to be used during the lectures. Students are expected to keep up with the assigned reading and be prepared toanswer questions on these readings during lecture. Please refer to the Bulletin of Information for Undergraduate Studies for the Department and Campus Policies.
TexbooksThere is no specific textbook. My lecture notes are available in the web at http://academic.uprm.edu/pcaceres
Recommended Reading: “Microstructure of Martensite” K. Bhattacharya
“Smart Materials Systems: Model Development” R.C. Smith
“Smart Electronic Materials: Fundamental and Applications” J. Singh.“Handbook of Modern Sensors: Physics, Designs, and Applications” J. Fraden.
ExamsAll exams will be conducted during normal lecture periods on dates specified dates. The final project due date is the date for the end of classes. There will be no final exam. Neatness and order will be taking into consideration in the grading of the exams. Up to ten points can be deducted for the lack of neatness and order. You must bring calculators, class notes and blank pages to the exams.
TENTATIVES DATESWeek Week
1 Overview of Smart Materials. 1
3
5
7
8 Shape Memory Alloys. 9 Shape Memory Alloys
13 Applications of Engineering Smart Structures and Products
14 Project Presentations
10
12
Classification of Smart Materials.
2 Crystal Structure & Microstructure Crystal Structure & Microstructure‐Quiz 1
4 Piezoelectric and ElectrostrictiveMaterials
Piezoelectric and ElectrostrictiveMaterials
6 Magnetostrictive and MagnetoelectricMaterials
Magnetostrictive and MagnetoelectricMaterials
Quiz 2
9 Shape Memory Alloys ‐ Quiz 3 Electrorheological and Magnetorheological Fluids
11 Sensor, Actuator and Transducer Technologies.
Sensor, Actuator and Transducer Technologies
15 Project Presentations
Projects
Project One
(1) Pyroelectricity(2)Piezoelectricity(3) Magnetostriction(4)Thermoelectricity(5) Shape Memory Alloys(6)Electrochromic materials
Presentation of at least 22 slides. It must cover the following: (a) physical principles, (b) tensor analysis, (c) two slides on devices and applications and (d) four numerical examples (problems).
Background
The field of smart materials has advanced rapidly in the last 15years, due to an increasing awareness of materials capabilities, the development of new materials and transducer design, and increasingly stringent design and control specifications in aerospace, aeronautics, industrial, automotive, bio‐medical and nanosystems.
Equally important for the advancement of the field is the development of models, numerical approximation techniques, and control design which accommodate the hysteresis and constitutivenonlinearities, inherent to the material.
The attributes that provide smart materials with unique actuatorand sensor capabilities are inexorably due to physical mechanisms that produce hysteresis, hence these mechanisms must be incorporated in models and control designs to achieve the unique performance capabilities offered by the compounds.
Smart systems are defined as ensembles whose dynamic can be monitored or modified by distributed sensors and actuators, in accordance with an integrated control law, to accommodate time‐varying exogenous inputs or changing environmental conditions.
Smart System or Structure
A smart structure is a system containing multifunctional parts that can perform sensing, control, and actuation; it is a primitive analogue of a biological body.
Smart Material Based Systems (SMBS) are defined as electro‐mechanical systems integrated with sensing, actuating, control and computational functions provided by such materials. Through system integration and compact design, systems with less complexity, lower cost and higher reliability can be built.
ActuatorsAdaptive
Response Shape Memory alloys, Piezoelectric
devices, MR fluids
ActuatorsAdaptive
Response Shape Memory alloys, Piezoelectric
devices, MR fluids
ElectronicsTransfer of Information
Signal detection and control.
ElectronicsTransfer of Information
Signal detection and control.
Sensors gather information
Optical fibersPiezoelectric
materials
Sensors gather information
Optical fibersPiezoelectric
materialsSmart System
EnvironmentStimuli
EnvironmentStimuli
Stimuli
Sensory FunctionControl Function
Adaptive Response
Smart materials referred to materials that will undergo controlled transformations through physical interactions. The ‘‘I.Q.’’ of smart materials is measured in terms of their ‘‘responsiveness’’ to environmental stimuli and their ‘‘agility.’’Responsiveness:how large is the amplitude change with respect to small stimulus.Agility:how fast is the respond.
Smart Material
Smart materials are materials that respond to their environment in a timely manner. These are materials that receive, transmit or process a stimulus and respond by producing a useful effect thatmay include a signal that the materials are acting upon it.
StimuliStrain Stress
TemperatureChemicals (pH stimuli)
Electric fieldMagnetic field
Hydrostatic pressureDifferent types of radiation
Effects caused byAbsorption of a protonA chemical reaction
Integration of a series of eventsTranslation or rotation of
segments within a molecular structure
Creation and motion of crystallographic defectsLocalized conformations
Alteration of localized stressStrain fields
Effects produced can be:Color change
Change in index of refractionChange in the distribution of
stresses and strainsVolume change
Another criterion for a material to be considered smart is that the action of receiving and responding to stimuli to produce a useful effect that must be reversible.
Active Actuator/Sensor MaterialsActuator materials are those capable to convert electrical, magnetic or thermal energy to mechanical energy, whereas sensor materialsare those that can provide the opposite conversion of energy.
Materials that have been labeled as smart include:
Material Effect
Piezoelectric Crystals which acquire a charge when compressed, twisted or distorted are said to be piezoelectric
Electrostrictive, Magnetostrictive and Elastorestrictive
The material quality of changing size in response to either an electric or magnetic field, and conversely, producing a voltage when stretched..
Electrorheological & magnetorheological
Fluids that can change state instantly through the application of an electric or magnetic charge
pH‐sensitive these are indicators that change colors as a function of pH
UV‐sensitive and Electrochromic
Electrochromism is defined as the ability of a material to change its optical properties when a voltage is applied across it.
Smart polymers Polymers that respond strongly to small changes in the external conditions.
Smart hydrogels Engineered response gels that shrink or swell by a factor of 1000, and that can be programmed to absorb or release fluids in response to almost any chemical or physical stimulus
Thermoresponsive ‐Shape memory alloys
the dominant smart material, change shape in response to heat orcold
Commonly encountered smart materials and structures can be categorized into three different levels: (i) single‐phase materials.Many ferroic materials and those with one or more large anomalies associated with phase‐transition phenomena.(ii) composite materials. Functional composites are generally designed to combine several functional materials to make a multifunctional composite, and (iii) smart structures. integration of sensors, actuators, and a control system that mimics the biological body in performing many desirable functions, such as synchronization with environmental changes, self‐repair of damages, etc.
Classification of Smart MaterialsThere are many different types of smart materials including piezoelectric, shape‐memory alloys, electro‐active conductive polymers, electrochromic materials, biomaterials, etc.
Table 3. Stimulus‐response matrix for selective responsive materials [after 16].
ResponseStimulus
Electrical Magnetic Optical Thermal Mechanical
Electrical ElectrochromicElectroluminescentElectro‐optic
Thermoelectric PiezoelectricElectrostrictiveER Fluids
Magnetic Magneto‐optic MR FluidsMagnetostrictive
Optical Photoconductor
Photochromic
Thermal ThermochromicThermoluminescent
Shape Memory
Mechanical
PiezoelectricElectrostrictive
Magnetostrictive
Mechanochromic Negative Poisson Ratio
.
Figure 2. Property‐Stimulus‐Response effects [after ref.18].
Materials science. Requires knowledge of composites, ceramics, metallic, alloys, gels, processing science, interface science, sensor/actuator materials, chiral materials, conducting and chiralpolymers, electrochromic materials, liquid crystals, molecular‐level smart materials, biomaterials.Sensing and actuation. Electromagnetic, acoustic, chemical and mechanical sensing and actuation, microelectromechanical systems (MEMS), sensor/actuator signal processing, smart sensors for materials and composites processing.Optical and electromagnetics. Optical fibre technology, active and adaptive optical systems and components.Structural. Smart skins for drag and turbulence control, other applications in aerospace/marine structures, civil infrastructures, transportation vehicles, manufacturing equipment.Control. Structural acoustic control, vibration control, adaptive structure capability, damage implications for structural control.Information processing. Neural network, data processing.
Disciplines in Smart Materials ‐ Inter‐disciplinary
Natural Sciences (Physics, Chemistry, Biology) and Mathematics
Creative IdeaInnovation
Mathematics & Modeling
Materials ScienceMaterials for device
components & packaging.Materials for signal transduction. Smart materials, Miniaturization,
Materials PropertiesMaterials for fabrication processes.
Mechanical EngineeringMachine components design.
Mechanisms & linkages.Thermomechanics:
solid & fluid mechanics, heattransfer, fracture mechanics.
Intelligent control.Micro process equipment design and manufacturing.
Assembly design
Electrical EngineeringPower supply. Electric systems design in electro-hydrodynamics. Signal transduction, acquisition,
conditioning and processing.Electric & integrated circuit design.
Electrostatic & EMI.
Natural Sciences (Physics, Chemistry, Biology) and Mathematics
Creative IdeaInnovation
Mathematics & Modeling
Materials ScienceMaterials for device
components & packaging.Materials for signal transduction. Smart materials, Miniaturization,
Materials PropertiesMaterials for fabrication processes.
Mechanical EngineeringMachine components design.
Mechanisms & linkages.Thermomechanics:
solid & fluid mechanics, heattransfer, fracture mechanics.
Intelligent control.Micro process equipment design and manufacturing.
Assembly design
Electrical EngineeringPower supply. Electric systems design in electro-hydrodynamics. Signal transduction, acquisition,
conditioning and processing.Electric & integrated circuit design.
Electrostatic & EMI.
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